Method of constructing arched structures



2 Sheets-Sheet 1 Feb. l0, i942.Y M H. MccLosKEY, JR

METHOD 0F CONSTRUCTING ARCHED STRUCTURES Filed Oct. 21, 1940 Feb. 10, i942. M. H. MccLosKEv, JR

METHOD OF CONSTRUCTING ARCED STRUCTURES Filed Ooi. 2l. 194C) 2 Sheets-,Sheet 2 Patented Feb. 10, 1942 l A METHOD 0F CONSTBUCTING ARCHE STRUCTURES Matthew H. McCloskey, Jr., Philadelphia, Pa.

Application October 21, 1940, Serial No. 362,165

20 Claims.

This invention relates to a method of producing arched structures, particularly of reinforced concrete, without the use of forms, and adapts itself admirablyfor use in the erection of underground enclosures.

Inasmuch as current engineering practice dictates the design and construction of forms as a necessary preliminary to any operation involving the pouring of concrete, the elimination of forms made possible by the present invention will appeal to those skilled in the art as a revolutionary advance. It is not uncommon for the design and construction of formsto represent a major part of the cost of a project and to require by far the greatest expenditure of time.

Hence where forms can be dispensed with, tremendous savings with respect to both of these elements will be realized.

In accordance with the present invention, it is contemplated that the earth be excavated to den'e peripheral slopes at substantially the natural angle of repose of the earth materials and a negative of the desired arched structure and its restraint, superimposing upon the excavation thus produced, a complete arched structure and .its restraint having a lower surface complementary to the-excavation, nishing` the upper surface of the arched structure and its restraint,

' and subsequently excavating earth from within the arched structure. Since the weight of the arched structure and its restraint is thus directly supported by the earth structure forming the bottom of the excavation, the removal of earth from within the structure need be delayed only sufciently long to permit the structure to attain adequate strength. In the case of reinforced concrete structures, this delay may be diminstructure is not adapted to the use of road ma- Achinery in its production, nor are the trench its original contour and elevation, thereby rendering it not only more resistant to explosives, but providing an excellent means of camouage. In addition, the handling VLof material can be minimized by covering the structure with the earth subsequently excavated from within the structure by suitable conveying apparatus.

Whereas it is known in the prior art to pour concrete directly info an excavation for the construction of an arch, as in the patent to Goodridge, 262,403, dated August 8, 1882, for example.

such a construction requires the preliminary dlgging of trenches land. pouring of trench walls, usually necessitating forms, and the subsequent construction of the arches themselves. Under these conditions, the entire outer surface of the walls readily accessible for application of the vacuum process. Moreover, the line of thrust of 'ah arch of the Goodridge type does not pass through its restraint into the earth without discontinuity, and as a consequence. special problems of design in bending and tension are encountered. Whereas continuously reinforced monolithic arched structures and restraints are contemplated in accordance with the present invention, similar construction `would hardly be ished appreciably" by the application of a rapid hardening process such as that disclosed in the patent to Billner, 2,046,867, dated July 7, 1936.

f As a matter of fact, where the vacuum process of the Billner patent is employed in cooperation with the present no-form method of construcvbe covered with earth to restore the ground to feasible with previously known methods where excavation and pouring are eiected in a-.series ofA independent and necessarily delayed operations.

The arched structures now proposed may ave 'spans which are greater than their clear he ghts,

and in some cases, one end wall, such as the rear one, may constitute in vertical section, an arch tied-in monolithically with the main structure, and a restraint tied-in with the restraint of the main structure, which, as an entirety, might be characterized as being of' segmental dome-like conguration. p

Where it is desired to impart a relatively smooth inner surface to the enclosure. a. weak cement grout or similar plastic material may be employed for filling any undesired depressions caused by the excavating operation or by the inherent nature of the soil and/or a layer of sheet material may be applied prior 'to the pouring of concrete. In such cases. after excavation of the earth from 'within the structure, the weak grout or thej like and/or the -sheet material may be stripped away readily.

A more complete understanding of the invention will be implemented by reference to a detailed description in conjunction with the accompanying drawings wherein:

Fig. 1 is a sectional elevation or profile of the ground to be excavated, with a broken line indication of the cut required by the particular structure to be fashioned;

Fig. 2 is a sectional elevationlof the ground after the excavation has been completed and prepared for the reception of the arched structure;

Fig. 3 is a sectional elevation of the reinforced concrete structure in position;

Fig. 4 -is a sectional elevation showing .the ground being restored to its original contour and elevation and the earth from beneath the span partially removed;

Fig. 5. is a sectional elevation of the completed structure including a floor; and

Fig. 6 is a longitudinal elevation of a structure produced in accordance with the present invention.

The geographical site of the proposed structure will ordinarily be selected to4 conform with desirable soil characteristics and topography. As d-epicted in Fig. 1 of the drawings, the'original ground surface 20 has been shown in conjunction with a broken line representation of the excavation required to serve as a negative for the desired structure at some particular location.

In Fig. 2, the excavation for the arched structure and its restraint has been represented as completed, the inclination of the walls or peripheral slopes 22 having been constructed to conform substantially to the angle of repose `of the natural soil thus obviating the need foi-forms at these points. When such formations as gravel or other readily sliding materials are encoun-.

tered, it may be desirable to employ grout -or other means to inhibit movement. Where it is desired to produce a relatively smooth interior nish for the structure. and/or where ground conditions render such a course necessary, any depressions 2l formed during the excavating op-l eration, may be lled with a weak cement grout 26, such as a 1:6 mixture or some similar composition, over which there is preferably provided a layer of sheet material 28 which will render the grout readily separable from the finished structure. When a. loose or porous subsoil is encountered during the excavating operation, the

use of a .similar bonding agent will serve to inhibit sliding of the earth structure, as well as fulllmg its smoothing function. In some cases,

y it may be desired to interpose only the sheet material 28, such aspaper, between the surface of the excavation andthe arched structure for the production of a smoother interior finish. To

lsimplify the drawings and their explanation, the

grout and sheet material have been illustrated 1n Fig. 2 only, but it will be understood that analogous materials maybe employed advantageously in many applications of the invention.

Further preparation of the site might be de- 'sirable or necessary under certain circumstances,

depending upon local soil characteristics, which may be termed the natural earth structure. In this connection, the term earth structure" is employed to describe the natural earth foundation or the natural earth foundation modified bythe presence of piles, caissons, or sheet piling. If warranted by the size of the project, ordinary road machinery will be preferred for the excavating operation.

After the soil has been'suitably prepared to serve as the sole form for the arched structure,

- continuous reinforcing elements 30 for the arched structure and its restraint, will be placed in the excavation, whereupon the concrete for the arched structure 32 and its restraint 3l may be poured in a single operation by the aid of existing road machinery. In speaking ofthe restraint throughout the present specification and claims, the technical significance recognized by those skilled in the art is intended. Since, as depicted in Fig. 3 of the drawings, the entire upper surface of the arched structure and its restraint is exposed, and at a relatively flat angie, at this stage, finishing operations may be effected with ordinary road machinery also. And the relatively flat angle referred to is Preferably approximately equal to the natural angle of repose of the concrete. At this point, the rapid hardening vacuum process of the Billner patent may be applied advantageously to the concrete with the benefits already explained.

After the concrete has attained Vstrength adequate to render the structure self-supporting, removal of the earth from within the structure may proceed. -Asl shown in Fig. 4 of the drawings, the removal of this material has been partially completed, there being a portion 36 yet to be disposed of. The arched structure is shown againin Fig. 5 as covered with a body of earth 38 to an elevation and ontour that conform to the original ground surface 20. This covering body of earth 38 may be a portion of that removed fromv within the structure, in which event, the use of suitable conveying machinery will promote further economy. Where this practice is followed, the earth removed from within the 4structure may be conveyed directly to its position above the structure with a minimum of loading and unloading'.

a layer of gravel 40 or other porous body has been represented, above which a concrete iioor slab or pavement 42 has been formed. 'I'he concrete iloor slab may be designed to act as the restraint or as any` part of the restraint. This can be accomplished by a suitably designed floor slab tied-in monolithically with the barrel of the arched structure. And at this stage of the construction, where the grout and/or sheet material ha`s been utilized, it may be stripped, scraped, or otherwise suitably removed to expose the iinished interior surface.

Whereas the structure mayassume a variety of forms in longitudinal elevation, a desirable one from many standpoints is that depicted in Fig. 6 of the drawings. The rear end wall 4I is closed in this instance by an arch which is tied-in monolithically with the main structure, and similarly, its restraint 46 is tied-in monolithically with the restraint of the main structure. The resulting structure considered as an entirety, may be assigned the form of a segmental dome-like housing which would be eminently suited to the storage of aircraft. Under these conditions, a suitable ramp 48 may be built as a continuation of the floor of the structure.

Whereas the use of the method in hangar construction has been mentioned repeatedly, it will be clear to those skilled in the art that the invention is admirably suited for the construction of many other types of structures. To mention only a few examples, it may be utilized for storehouses, tanks, culverts, arches, air raid shelters and powder magazines.

I claim: 1. The method of `constructing an arched ture comprising forming an excavation in the earth toproduce peripheral slopes at substantially the natural angle of repose of the earth materials and to define a negative of the entire lower surface of an arched structure and its restraint in a single operation, laying therein a complete arched structure and its restraint hav- `ing a lower surface complementary to the excavation with the line of thrust of said structure passing through its restraint int the earth without discontinuity, the earth forming the' bottom of said excavation directly supporting the entire weight of said arched structure and its restraint, finishing the upper surface of said structure and its restraint while thus supported, and subsequently excavating the earth from within said arched structure. v

3. The method of constructing an arched structure comprising forming an excavation in the earth to produce peripheral slopes at substantially the natural angle of repose of the earth materials and to dene a negative of the entire lower surface of an arched structure and its Vrestraint in a .single operation, laying therein a complete arched structure and its restraint having a lower surface complementary to the excavation, theA earth forming the bottom of said excavation directly supportingthe entire weight of said arched structure and its restraint, nishing the upper surface of said arched structure and its restraint while thus supported, subsequently excavating the earth from within said arched structure and transferring earthpexcavated from within the arched structure to a position above and covering the structure.

4. tThe method of constructing an arched structure Vcomprising vforming an excavation in lstructure comprising forming an excavation in materials and toetlne a negative of the entire lower surface of ran arched structure and its restraint in a single operation and to a depth greater than the thickness of crown of said arched structure, 4laying therein a complete arched structure and its restraint having a lower surface complementary to the excavation, the earth forming `the bottom of said excavation directly supporting the entire weight of said arched structure and its restraint, finishing the upper surface of said arched structure and its restraint while thus supported, subsequently excavating the earth from within said arched structure and covering the structure with earth.

6. The method of constructing an Yarched structure comprising forming an excavation in the earth to produce peripheral kslopes at substantially the natural angle of repose of the earth materials and to define a negative of the entirelower surface of an arched structure and its restraint in a single operation and to a depth greater than the thickness of crown of said arched structure, laying therein a complete arched structure and its restraint having a lower surface complementary to the excavation, the earth forming the bottom` of said excavation directly supporting the entire weight of said arched structure and its restraint, nishing the upper surface of said varched structure and its restraint while thus supported, subsequently excavating the earth from within said arched structure and transferring earth excavated from within said arched structure to a position abovel the structure to cover the same.

7. The method of constructing an arched structure comprising forming lan excavation ini the earth to define peripheral slopes atsubstantially the natural angle of repose of the earth materials and a negative of the entire lower surface of'an arched structure and its restraint in a single operation, pouring concrete therein to form a complete arched structure and its restraint having a lower surface complementary to the negative excavation, the earth forming the bottom of said excavation directly supporty ing the entire weight of said arched structure the earth to produce peripheral slopes at substantially the natural angle of repose of the earth materials and to denne a negative of the entire lower surface of an arched structure and its restraint in a single operation, pouring therein a complete arched structure and its restraint having a lower surface complementary to theexcavation, said excavation serving as the sole form for the poured material, the earth forming the bottom of said excavation directly supporting the entire weight of saidv arched structure and its restraint, finishing the upper surface of said arched structure and its restraint while thus supported, and subsequently excavating the earth from within said arched structure.

5.The methodA of constructing an arched structure comprising forming an excavation in the earth to produce peripheral slopes at sub-- stantiallythenaturalangleofreposeoftheearth and its restraint. nishing the upper surface of said arched structure and its restraint while thus supported, and subsequently excavating the earth from within said arched structure.

8. The method of constructing an arched structure comprising forming an excavation in the earth to produce peripheral'slopes at substantially the natural angle of repose of the earth materials and to denne a negative of the entire lower surface of an arched structure and its restraint-in a single operation, pouring concrete thereinto form a complete arched structure and its restraint having a lower surface complementary to the excavation, the earth forming the bottom of said excavation directly supporting the entire weight of said arched structure .and its restraint, nnismng the upper surface of said arched structure and its restraint with -road paving machinery while thus supported, and subsequently excavating the earth from within said arched structure.

9. The .method of 'constructing an arched' structurecomprising forming an excavation in the earth to produce peripheral slopes at substantially the natural angle of repose of the earth materials and to define a negative of the entire lower surface of an arched structure and its restraint-in a single operation, applying continuous reinforcement to the surface thus defined, pouring concrete therein to form a complete', reinforced, interlocked arched structure and restraint having a lower surface complementary to .the excavation, the earth forming the bottom of said excavation directly supporting the entire weight of said arched structure and its restraint, finishing'the upper surface ofsaid arched structure and its restraint while us supported, and subsequently excavating the arth from within said arched structure.

l0. The method of constructing an arched structure comprising forming an excavation in the earth to define a negative of the entire lower surface of an arched structure and its restraint in a single operation, pouring concrete therein to form a complete arched structure and its restraint hav-,ing a lower surface complementary to the excavation, the earth forming the bottom of said excavation directly supporting the entire weight of said arched structure and its restraint, finishing the upper surface of said arched structure and its restraint while`thus supported, removing a portion yof the water from said concrete by a vacuum process, and subsequently excavating the earth from within said arched structure.

11. The method of constructing an arched structure comprising forming an excavation in the earth to produce peripheral slopes at substantially the natural angle of repose of the* earth materials and to dene a negative of the entire lower surface of an arched structure having a span greater than its clear height and its restraint in a single operation, laying therein a complete arched structure and its restraint having a lower surface complementary to the excavation, the earth forming the bottom of said excavation directly supporting the entire weight oi' said arched structure and its restraint, finishing the upper surface of said arched structure and its restraint while thus supported, and subsequently excavating the earth from within said arched structure.

12. The method of constructing an underground structure comprising forming an excavation in the earth to produce peripheral slopes at substantially the natural angle of repose of the earth materials and to denne a negative of the entire lower surface of an arched structure and its restraint in a single operation, pouring concrete thereino form a complete arched structure and its restraint having a lower surface complementary to the excavation and an upper surface inclined at a relatively flat angle, the earth forming the bottom of said excavation directly' supporting the entire weight of said arched structure and its restraint, finishing the upper surface of said arch and its restraint while thus supported, subsequently excavating the earth from Within said arched structure and covering said structure with earth.

13. The method of constructing an uncle ground structure comprising forming an excavation in the earth to dene a negative of the entire lower surface of an arched structure and its restraint in a single operation, pouring concrete therein to form a complete arched structure and its restraint having a lower surface complementary to the excavation, the earth forming the bottom of said excavation directly supporting the entire weight of said Varched structure and its restraint, finishing the upper surface of said arched structure and its restraint While thus supported, subsequently` excavating the earth from within said arched structure and covering said arched structure with earth removedfrom within said structure.

14. The method of constructing an underground structure comprising forming an excavation in the earth to produce peripheral slopes at substantially the natural angle of repose of the earthmaterials and 'to define a negative of the entire lower surface of an arched structure and its restraint in a single operation and to such a depth that the nished structure will be entirely below the original earth surface, laying therein a complete arched structure and its restraint having a lower surface complementary to the excavation, the earth forming the bottom of said excavation directly supporting the en tire weight of said arched structure and its re straint, finishing the upper surface of said arched structure and its restraint while thus supported, subsequently excavating the earth from within said structure and restoring the earth above said structure to substantially its originel contour and elevation.

15. The method of constructing an arched structure comprising forming an excavation in the earth to define a negative of the entire lower surface of an arched structure and its restraint in a single operation, pouring concrete therein in a single operation to form a complete arched structure and its restraint having a lower surface complementary to the excavation, the earth forming the bottom of said excavation directly supporting the entire weight of said arched structure and its restraint, finishing the upper surface of said structure and its restraint while thus supported, and subsequently excavating the earth from within said structure.

16. The method of constructing an enclosure comprising forming an excavation in the earth to define a negative of the entire lower surface of an arched structure, its restraint, and a closed rearwall in a single operation, pouring concrete therein to form a complete arched structure, its restraint, and a closed rear wall having a lower surface complementary to the excavation, the

' earth forming the bottom of said excavation directly supporting the entire Weight of said arched structure, its restraint, and rear wall, finishing the upper surface of said arched structure, its restraint, and rear Wall while thus supported, and subsequently excavating the earth from within said enclosure.

17. The method of constructing an arched structure comprising forming an excavation in the earth to dene a negative of the entire lower surface of an arched structure and its restraint in a single operation, smoothing the surface thus produced with a layer of relatively weak moldable material, pouring concrete upon said surface to form a complete arched structure and its restraint having a lower surface complementary to the smoothed surface of the excavation, the earth forming thev-bottom Vof said excavation directly supporting the entire weight of said arched structure and its restraint, finishing the upper surface of said arched structure and its restraint while thus supported, subsequently excavating the earth from within said arched structure and removing the relatively weak moldable material.

18. The method of constructing an arched structure of substantially segmental dome-like configuration comprising forming an excavation in the earth to produce peripheral slopes at sub# stantially the natural angle of repose of the earth materials and to define a negative of the ing the earth from within said structure.

19. The method of cnstructing an arched structure comprising forming an excavation in the earth to deiine a negative of the entire lower surface of an arched structure, covering the surface thus produced with a layer of sheet matefrom within said' structure, and stripping said sheet material from the interior of said structure. 20. 'I'he methodof constructing an arche structurel comprisinglforming an excavation in the earth to produce peripheral slopes ax substantially the natural angle of repose oi' the earth materials and to deiine a negative of the entire lower surface of the structure and its restraint in a single operation, smoothing the surface thus produced with a moldable material, covering the rial, pouring concrete upon said material to form l a complete arched structure and its restraint as a monolith having a lower surface complementary to the excavation, the earth serving as the sole form for said arched structure and its restraint, the upper surface oi said arched structureI and its restraint .while thus supported, subsequently excavating the earth 4smoothed surface with a layer of sheet mate-- rial, pouring concrete therein to form a complete arched structure and its restraint having a lower surface complementary to the excavation, the earth forming the bottom of said excavation directly supporting the entire weight of said structure and its restraint, iinishing the upper surface of said structure and its restraint while thus supported, excavating the earth from within the structure, covering the structure with earth,

and stripping said moldable and sheet materials from the interior of said structure. v

H. MCCLOSKEY, JR. 

